1. Field of the Invention
This invention relates to a change speed apparatus for a fishing reel, and more particularly to a fishing reel in which a fishing line takeup member such as a spool is driven in varied speeds.
2. Description of the Prior Art
A known fishing reel of this type is disclosed in Japanese Patent Publication Kokai No. 1989-277441, for example. The construction proposed in this publication comprises a handle-rotatable sleeve rotatable by a handle, and an output shaft rotatably supported in the sleeve and having a main gear. A planetary gear mechanism is provided which includes a sun gear mounted on the output shaft, planet gears supported on the handle-rotatable sleeve and meshed with the sun gear, and a ring gear rotatably supported on a reel body and having internal teeth meshed with the planet gears. The reel body has a stopper pawl engageable with engaging teeth defined peripherally of the ring gear. When the handle is turned in a direction to wind up a fishing line with the stopper pawl engaging one of the engaging teeth to lock the ring gear against rotation, the handle-rotatable sleeve is rotated, and the output shaft having the sun gear is rotated in acceleration with the planet gears rotating, whereby the spool is driven at high speed through the main gear. On the other hand, when the handle is turned in the direction to wind up the fishing line with the stopper pawl disengaged from the engaging teeth to render the ring gear rotatable, the handle-rotatable sleeve is directly connected, for unitary rotation, to the output shaft through a one-way rotation drive mechanism. At this time, the ring gear meshed with the planet gears follows rotation of the sun gear, to be free from the accelerating action of the planetary gear mechanism, whereby the spool is driven at low speed through the main gear.
Where the speed is changed by using a planetary gear mechanism as above, the speed ratio between high speed and low speed may be reduced by reducing the pitch diameter of the planet gears. However, there is a limitation to reduction of the pitch diameter of the planet gears by reason of the strength of the planet gears. Consequently, only a limited freedom is allowed for selecting a gear ratio, and the speed ratio cannot be reduced below a certain value. The above construction has a further disadvantage of being costly since it is very difficult to shape the internal teeth of the ring gear with high precision.